The present invention relates to an aerogel-based thermal insulating material.
Aerogels are defined as dry gels generally having pores of nanometric volume. This type of material is obtained by the supercritical drying of organogels which makes it possible to eliminate the solvent while retaining the porous texture of the liquid gel.
In application WO2010/133798, the inventors previously described a series of organogelators derived from natural amino acids, allowing the formation of organic physical gels with a low molecular weight. The aerogels obtained from these organogelators by extraction of the solvent are mesoporous nanostructured materials which have remarkable properties, in particular in terms of specific surface area, very low solid contribution and thermal stability over time due to its very high hydrophobicity.
However, the aerogels described in application WO2010/133798 have neither the mechanical strength nor the density required in order to be used alone for certain applications, in particular such as insulating material in buildings.
As a result, there exists the need to develop thermal insulating materials having both the aerogel properties described in WO2010/133798, in particular hydrophobicity, and a better stiffness and physical strength.
Application US2002/0094426 describes a composite comprising an aerogel and a support matrix, for example a batting, obtained by implementing supercritical CO2 extraction on said support matrix impregnated with a solution of a material capable of forming an inorganic gel, such as a silica gel or a polymeric gel.
Given that these gels are chemical gels held together by irreversible covalent bonds, the use thereof for impregnating a matrix presents certain drawbacks. In fact, once gelation is complete, it is no longer possible to correct a defect that has occurred during impregnation of the support matrix. Moreover, the composites described in this application require an additional chemical treatment in order to make the final products hydrophobic. In addition, polymerization of the polymeric gels also requires the addition of chemical complements.
Therefore, there is an industrial benefit in proposing thermal insulating materials which can be more easily manufactured.